/*-----------------------------------------------File Info------------------------------------------------
** File Name:               caluculations.c  
** Last modified date:      2016.07.22
** Last version:            V0.1
** Description:             
**--------------------------------------------------------------------------------------------------------            
** Created date:            2016.09.07
** author:                  YLY
** Version:                 V0.1
** Descriptions:            常用运算函数
**--------------------------------------------------------------------------------------------------------
*/
/*************************************************************
* 	include 
* 	头文件	
*************************************************************/
/*   用户头文件      */
#include "arithmetic.h"

const unsigned char keyBox[256] =
{
	0xEF, 0xE3, 0x27, 0x86, 0x58, 0x6A, 0xA3, 0x71, 0xEE, 0x56, 0xC2, 0x7F, 0xB1, 0x16, 0xAF, 0x10, 
	0x44, 0x25, 0xA6, 0xDE, 0x72, 0x09, 0xD2, 0x43, 0x90, 0xD5, 0xA7, 0x53, 0xD1, 0xD6, 0x14, 0x5B, 
	0xF1, 0x42, 0x2A, 0x36, 0x5D, 0xCE, 0xA0, 0x31, 0x29, 0xA8, 0x47, 0x83, 0xD3, 0x80, 0x02, 0xAB, 
	0x66, 0xC7, 0x6E, 0x34, 0x1C, 0xB5, 0x49, 0xE8, 0x22, 0xFE, 0xA1, 0x3D, 0xE0, 0x3E, 0x45, 0x6B, 
	0x6D, 0x0F, 0x8F, 0x7C, 0xC9, 0x8A, 0x11, 0x82, 0xEC, 0x3B, 0xAA, 0x61, 0x76, 0x84, 0x8D, 0xB8, 
	0xA2, 0x75, 0x74, 0x39, 0x55, 0x78, 0xF7, 0xF0, 0x69, 0xB2, 0x88, 0x57, 0x4B, 0xA9, 0xD0, 0x40, 
	0x0C, 0xC5, 0xC8, 0x60, 0x03, 0x65, 0x05, 0xF6, 0xD4, 0x30, 0x48, 0x54, 0x87, 0xE4, 0xF3, 0xCC, 
	0x6C, 0x2D, 0x68, 0xB6, 0x79, 0x62, 0xFF, 0x23, 0x9C, 0x7D, 0x4F, 0x96, 0x21, 0x0D, 0x95, 0x6F, 
	0x06, 0x97, 0xB9, 0xF8, 0x73, 0x8C, 0xA5, 0x2F, 0xBE, 0xBF, 0x35, 0x1B, 0x13, 0xB7, 0xE7, 0xB0, 
	0xB4, 0xAD, 0x91, 0x0E, 0x1E, 0xBC, 0x67, 0xE2, 0xEA, 0x9F, 0x9B, 0x7A, 0xC4, 0x2E, 0x3C, 0x52, 
	0xD9, 0xDF, 0x37, 0xFB, 0x63, 0xAE, 0xE5, 0x41, 0x9E, 0xCB, 0xF9, 0x93, 0x2C, 0x24, 0xBB, 0xB3, 
	0x08, 0xBD, 0x51, 0x9A, 0x0A, 0x99, 0x18, 0x77, 0xC1, 0xEB, 0xF2, 0xCD, 0xAC, 0xBA, 0x33, 0xFC, 
	0x17, 0x81, 0x7B, 0xE9, 0x3A, 0x00, 0x4E, 0xC6, 0xC0, 0x50, 0xE6, 0xF5, 0x3F, 0x94, 0x1D, 0xF4, 
	0x70, 0x1F, 0xFA, 0xCF, 0xDD, 0x4A, 0x5A, 0x59, 0x15, 0x85, 0x92, 0x4C, 0x9D, 0x38, 0x12, 0xED, 
	0xCA, 0xA4, 0x46, 0x4D, 0x28, 0xE1, 0x20, 0xC3, 0x32, 0x98, 0x5F, 0xDA, 0x8E, 0xDB, 0xFD, 0x5E, 
	0x7E, 0xD8, 0x19, 0x07, 0x64, 0x01, 0x89, 0x5C, 0x8B, 0x26, 0x04, 0xDC, 0x0B, 0x1A, 0xD7, 0x2B
};

/**
*	逆序                                                                                                      
**/
void reverseData(uint8_t *data, uint16_t size)
{
	uint8_t tmp;
	uint16_t i, num, position;
	
	num = size/2;
	for(i=0; i<num; i++)
	{
		position = size-i-1;
		tmp = data[i];
		data[i] = data[position];
		data[position] = tmp;
	}	
}


#if 0
static void swap(uint8_t *a, uint8_t *b) 
{
	uint8_t t = *a;
	*a = *b;
	*b = t;
}

/**
*	rc4_KSA
*	rc4密钥盒子生成器
*      
* 参数：*Data——当前数据缓冲区指针     
*       len——数据长度 
*		SecretKeys——密钥
*
* 输出: *Data——加解密后的数据  
* 返回：计算结果                                                                                                        
**/
void rc4_KSA(uint8_t *s, const char *key, uint32_t len) 
{
    uint32_t i,j;
	for(i = 0; i < 256; i++) 
	{
		s[i] = i;	
	}
	j = 0;
    for (int i = 0; i < 256; i++ ) 
	{
        j = (j + s[i] + *(key + i % len)) % 256;
        swap(s + i, s + j);
    }
}
#endif
/**
*	rc4_crypt
*	rc4加解密算法,简化版本(非标准RC4,为了节约内存少了空间交换的逻辑)
*      
* 参数：*Data——当前数据缓冲区指针     
*       len——数据长度 
*		SecretKeys——密钥
*
* 输出: *Data——加解密后的数据  
* 返回：计算结果                                                                                                        
**/
void rc4_crypt(uint8_t *Data, uint64_t Len, uint32_t SecretKeys)
{
    uint32_t i = 0, j = 0, t = 0;
    uint64_t k = 0;
   
    j = SecretKeys;
    for (k = 0; k<Len; k++)
    {
        i = (i + 1) % 256;
        j = (j + keyBox[i]) % 256;
		//swap(keyBox+i,keyBox+j);(非标准RC4,为了节约内存少了空间交换的逻辑)
        t = (keyBox[i] + keyBox[j]) % 256;
        Data[k] ^= keyBox[t];
    }							
}



/**
* rec_ucCheckXor 异或校验                             
* 参数：*pBuf——当前数据缓冲区指针     
*       len——数据长度             
* 返回：计算结果                                                                                                        
**/
uint8_t ucBufCheckXor(uint8_t *pucBuf, uint16_t usLen)
{
   uint8_t ucCheckXor=0;
   while(usLen--) 
       ucCheckXor ^= *pucBuf++;
   return  ucCheckXor;
}


/**
* rec_check sum 求和                             
* 参数：*pBuf——当前数据缓冲区指针     
*       len——数据长度             
* 返回：计算结果                                                                                                        
**/
uint8_t ucBufCheckSum(uint8_t *pucBuf, uint16_t usLen)
{
   uint8_t checkSum=0;
   while(usLen--) 
       checkSum += (uint8_t)*pucBuf++;
   return  checkSum;
}

/**
* rec_check sum 求和                             
* 参数：*pBuf——当前数据缓冲区指针     
*       len——数据长度             
* 返回：计算结果                                                                                                        
**/
uint16_t usBufCheckSum(uint8_t *pucBuf, uint16_t usLen)
{
   uint16_t checkSum=0;
   while(usLen--) 
       checkSum += (uint8_t)*pucBuf++;
   return  checkSum;
}

/**
* rec_check sum 求和                             
* 参数:*pBuf当前数据缓冲区指针    
*       len数据长度           
* 返回:计算结果                                                                                                        
**/
uint32_t uiBufCheckSum(uint8_t *pucBuf, uint16_t usLen)
{
   uint32_t uiCheckSum=0;
   while(usLen--) 
       uiCheckSum += (uint32_t)*pucBuf++;
   return  uiCheckSum;
}

#if 0

//MODBUS CRC-16表 8005 逆序
const uint16_t gMcRctable16[256] =
{
	0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
	0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
	0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
	0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
	0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
	0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
	0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
	0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
	0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
	0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
	0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
	0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
	0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
	0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
	0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
	0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
	0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
	0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
	0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
	0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
	0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
	0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
	0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
	0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
	0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
	0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
	0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
	0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
	0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
	0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
	0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
	0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
};

//函数功能：计算CRC16
//参数1：*pData  16位CRC校验数据，
//参数2：nLength 数据流长度
//参数3：init    初始化值
//参数4：ptable  16位CRC查找表

//逆序CRC计算
static uint16_t usGetRevCrc(uint8_t * pData, uint16_t nLength, 
					 uint16_t init, const uint16_t *ptable )
{
  uint16_t cRc_16 = init;
  uint8_t temp;

  while(nLength-- > 0)
  {
    temp = cRc_16 & 0xFF; 
    cRc_16 = (cRc_16 >> 8) ^ ptable[(temp ^ *pData++) & 0xFF];
  }

  return cRc_16;
}

//正序CRC计算
uint16_t GetCrc_16(uint8_t * pData, uint16_t nLength, 
					uint16_t init, const uint16_t *ptable)
{
  uint16_t cRc_16 = init;
  uint8_t temp;

  while(nLength-- > 0)
  {
    temp = cRc_16 >> 8; 
    cRc_16 = (cRc_16 << 8) ^ ptable[(temp ^ *pData++) & 0xFF];
  }

  return cRc_16;    
}

//Demo -- modbus-crc16测试
uint16_t CRC_GetModbus16(uint8_t *pdata, int len)
{
  return usGetRevCrc(pdata, len, 0xFFFF, gMcRctable16);
}
#endif


